The science of aging, though young in comparison to the science of development, has advanced considerably during the past three decades. Up until 1980, most of the research that had been done was on the physiological and biochemical aspects of aging. The information obtained from this research was covered in my book, Biochemistry of Ageing, published by Academic Press in 1980. Since the development in the early 1980s of genetic engineering technology, the research on aging has concentrated on the role of the gene and the changes that occur at the genetic level during the aging process. Much of this research is being focused on the genes that are expressed in either a greater or lesser degree in old age, the changes that occur in the promoters of genes, the trans-acting factors that alter with age, and the genes that vary in expression during aging under stress. However, with all the research that has been aimed at elucidating the changes in genes, we still do not know how many genes are involved in the aging process, nor do we know the specific genes responsible for aging. Also, whether the same set of genes undergoes alterations in expression in all organs during aging or whether there are tissue-specific alterations in the expression of genes remain to be answered.

In Genes and Aging I have attempted to assemble the information on age-related changes in genes that has appeared primarily in the last ten years, since it is during this period that biochemists and molecular biologists have concentrated on this problem.